test(app): 新增 node:test 單元與整合測試並加入 test 指令

app/index.test.js

@@ -0,0 +1,79 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import {
+  truncateDiff,
+  fallbackSummary,
+  buildResolveBranchName,
+  buildResolveBody,
+} from './index.js';
+
+test('truncateDiff: 內容在上限內不截斷', () => {
+  const { diff, truncated } = truncateDiff('abc', 100);
+  assert.equal(diff, 'abc');
+  assert.equal(truncated, false);
+});
+
+test('truncateDiff: null/空字串回傳空字串且不截斷', () => {
+  assert.deepEqual(truncateDiff(null, 100), { diff: '', truncated: false });
+  assert.deepEqual(truncateDiff('', 100), { diff: '', truncated: false });
+});
+
+test('truncateDiff: 超過上限時截斷並標示', () => {
+  const big = 'x'.repeat(50);
+  const { diff, truncated } = truncateDiff(big, 10);
+  assert.equal(truncated, true);
+  assert.ok(diff.startsWith('xxxxxxxxxx'));
+  assert.ok(diff.includes('已截斷'));
+});
+
+test('fallbackSummary: 取首個 commit 當標題', () => {
+  const s = fallbackSummary({
+    source: 'feature',
+    target: 'develop',
+    commitMessages: '- feat: 新增功能\n- fix: 修正',
+    diffStat: ' a.js | 2 +-',
+  });
+  assert.equal(s.title, 'feat: 新增功能');
+  assert.ok(s.description.includes('## 變更摘要'));
+  assert.ok(s.description.includes('a.js'));
+});
+
+test('fallbackSummary: 無 commit 時退回 Merge 標題且描述非空', () => {
+  const s = fallbackSummary({
+    source: 'feature',
+    target: 'develop',
+    commitMessages: '',
+    diffStat: '',
+  });
+  assert.equal(s.title, 'Merge feature into develop');
+  assert.ok(s.description.includes('(無)'));
+  assert.ok(s.description.length > 0);
+});
+
+test('buildResolveBranchName: 含前綴並淨化非法字元', () => {
+  const name = buildResolveBranchName('develop', 'feature/x y');
+  assert.ok(name.startsWith('resolve-conflict/'));
+  assert.ok(name.includes('-into-'));
+  // 空白等非法字元被替換為 -
+  assert.ok(!/\s/.test(name));
+});
+
+test('buildResolveBranchName: 過長 target/source 仍遠低於 255', () => {
+  const long = 'a'.repeat(500);
+  const name = buildResolveBranchName(long, long);
+  assert.ok(name.length < 255);
+});
+
+test('buildResolveBody: 含衝突檔案清單與人工檢查清單', () => {
+  const body = buildResolveBody({
+    source: 'feature',
+    target: 'develop',
+    resolveBranch: 'resolve-conflict/develop-into-feature',
+    files: ['a.js', 'b.js'],
+    summary: { title: 't', description: '摘要內容' },
+  });
+  assert.ok(body.includes('- `a.js`'));
+  assert.ok(body.includes('- `b.js`'));
+  assert.ok(body.includes('合併前人工檢查清單'));
+  assert.ok(body.includes('摘要內容'));
+});